the Royal Road was a designation assigned to any road administered by the Spanish Crown, including through its viceroys. During the Spanish Empire, several such roads ran through the expanses of Central and South America (as well as California). A famous example is the 966km long * California Mission Trail* connecting Mission San Diego de Alcalá to Mission San Francisco Solano.
One of these roads connected Buenos Aires to Lima. What is the course of this route? Is there any map depicting its path? I couldn't find any image or map that covers the road nor basic information about it.